1. Field of the Invention
This invention relates to closure means for containers and more particularly to an automatic closure for a deformable container or a container where pressure is otherwise on flowable material therein.
2. Description of the Prior Art
Self-closing automatic closure members for containers such as toothpaste tubes and the like are well-known in the art. Such closures are generally sealed when there is no pressure on the deformable container, but upon pressure being applied to such deformable container, the closure member opens allowing the flowable material contained therein to be discharged. Shampoos, cosmetics, condiments and other products often contained in plastic bottles have been envisioned to use such automatic closure caps. An example of a self-closing closure member is seen in Nilson, U.S. Pat. No. 4,141,474 which discloses containers having diaphragm members upon which pressures to allow the discharge of the flowable material contained therein when pressure is exerted on the containers. Other examples of such self-closures utilize valve members which have movable parts such as disclosed in Laauwe, U.S. Pat. No. 4,057,177 and yet other self-sealing caps for containers utilize the expansion of bellows to unseal the openings for release of the materials within the container such as seen in Testa, U.S. Pat. No. 4,032,051. Some of the devices found in the prior art are extremely complex and costly to produce. An example of such a complex pressure-responsive closure can be found in Feldburg, U.S. Pat. No. 2,607,515. It is to avoid the complexity of the prior art and yet provide a simple and reliable design for an automatic closure that the instant invention was developed.